a) Field of the Invention
This invention relates to a novel thermosetting resin composition having excellent impact resistance and toughness.
b) Description of the Prior Art
Thermosetting resins having an imide structure have been used widely to date in the industry for their superb electrical insulating properties and heat resistance and the excellent dimensional stability of their molded articles.
Although thermosetting resins making use of an aromatic bismaleimide are insoluble and infusible materials having excellent heat resistance, they are accompanied by the drawbacks that they are poor in impact resistance and toughness.
As a method for improving the impact resistance and toughness of an aromatic bismaleimide, it has hence been attempted to use the aromatic bismaleimide together with an aromatic diamine. A polyaminobismale-imide resin composed of N,N'-(4,4'-methylene-diphenylene)bismaleimide and 4,4'-diaminodiphenyl-methane may be mentioned by way of example. It is however still unsatisfactory in impact resistance and toughness.